502 Algae. 



In winter and spring northern forms of plankton-organisms, 

 Tricho- and 6"//'« - plankton, prevail, in summer and autumn 

 temperate forms, Stylt- and D/ö(ym«5-plankton ; the number of 

 species is greatest in autumn and then in spring; at the same 

 seasons the quantity of the piankton is the iargest. 



The diagrams show the number of the organisms, both all 

 species taken together and the species of the four above men- 

 tioned types taken separately, for every month of the years 

 1896 — 1903; other diagrams give an idea of the quantity of 

 the piankton from 1902 tili 1904. 



Further the papers contain a list of all the forms hitherto 

 found at the two stations and arranged after the 4 types, to 

 which two others, viz. Baltic piankton and piankton incertae 

 sedis, have been added. 



This list shortly resumes the seasons, in which each spe- 

 cies has been found and if and when they predominate. 



C. H. Ostenfeld. 



Gepp, A. and E. S., More Antarctic Algae. (Journal of 

 Botany. XIV. July 1905. p. 193—196. Plate 472.) 



The authors, having received more material coUected by 

 the Scottish Antarctic Expedition, publish an account of 6 more 

 species from the S. Orkneys, five of these being new records. 

 One of them is a new species, Hydrolapathiim stephauocarpiim, 

 which mainly differs of H. sangiiineiun in having a cystocarp 

 more or less clothed with simple, subulate appendages. The 

 tetraspores of Leptosarca simplex having been found on the 

 new material, the authors transfer the species to Gracilaria, as 

 G. simplex^ leaving it for the time being in the section Podeiim. 

 Two other species, one of doubtful affinity and sterile, and the 

 other a queried Callophyllis variegata are fully described and 

 figured. E. S, Gepp-Barton. 



JÖRGENSEN, E., Diatoms in Bottom Samples from 

 Lofoten andVesteraalen in: 0. Nordgaard, Hydro- 

 graphical and Biological Investigations in Nor- 

 wegian Fiords. (Bergens Museums Skrifter. Bergen 1905. 

 Folio, p. 195—225.) 



The author has examined the diatoms in a large material of bottoin 

 samples from the fiords of the NW. coast of Norway, especially from 

 Lofoten and Vesteraalen. The examination is based upon slides 

 prepared by Thum in Leipzig; consequently is has not been possible 

 to discern between living (recent) and fossil species. 



He gives a long list of the species (293) observed ; many critical 

 remarks of systematical value are added; the list contains also the 

 places within the area where each single species has been observed, 

 and finally the geographical distribution of each species. 



Of his general remarks on the character of the Diatom flora we 

 extract the following: The arctic forms are rare, and the flora, on the 

 whole, has a much more southern character than would be expected 

 from the geographical position. This is in sharp contra-distinction to 

 the Diatom flora of the piankton at least in the spring, when the actual 



